Anion-exchange membrane direct ethanol fuel cells: Status and perspective

Abstract

Direct ethanol fuel cells (DEFCs) are a promising carbon-neutral and sustainable power source for portable, mobile, and stationary applications. However, conventional DEFCs that use acid proton-exchange membranes (typically Nafion type) and platinum-based catalysts exhibit low performance (i.e., the state-of-the-art peak power density is 79.5 mW/cm² at 90°C). Anion-exchange membrane (AEM) DEFCs that use low-cost AEM and non-platinum catalysts have recently been demonstrated to yield a much better performance (i.e., the state-of-the-art peak power density is 160 mW/cm² at 80°C). This paper provides a comprehensive review of past research on the development of AEM DEFCs, including the aspects of catalysts, AEMs, and single-cell design and performance. Current and future research challenges are identified along with potential strategies to overcome them.

Keywords

fuel cell / direct ethanol fuel cells / anion-exchange membrane / ethanol oxidation reaction / oxygen reduction reaction / cell performance

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Acknowledgements

This work was supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. 623709).

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T.S. Zhao is a Professor of Mechanical Engineering and the Director of Center for Sustainable Energy Technology at the Hong Kong University of Science & Technology (HKSUT). As an internationally renowned expert in energy technology, he presently focuses his research on fuel cells, multi-scale multiphase heat/mass transport with electrochemical reactions, and computational modeling. As of October 2010, he has published more than 150 papers in prestigious journals in the fields of energy science and engineering with SCI citations of more than 2850 times and H-index of 30. He has received a number of recognitions for his research and teaching, including the Bechtel Foundation Engineering Teaching Excellence Award at HKUST in 2004, the Overseas Distinguished Young Scholars Award by National Natural Science Foundation of China in 2006, Fellow of the American Society of Mechanical Engineers (ASME) in 2007, the Croucher Senior Fellowship award from the Croucher Foundation in 2008, and the Yangtze River Chair Professorship by the Chinese Ministry of Education in 2010. In the international community, Prof. Zhao serves as Editor-in-Chief of Advances in Fuel Cells, Series Editor, Energy & Environment (Royal Society of Chemistry), Asian Regional Editor of Applied Thermal Engineering, and as a member of the Editorial Board for more than 18 International Journals.

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